Comprehensive Study Guide to Formal and Informal Fallacies

Fundamentals of Logical Fallacies

• Definition of Fallacy: A defect in an argument that results from a mistake in reasoning or the creation of an illusion that makes a bad argument appear good.

• Universal Occurrence: Both deductive and inductive arguments may contain fallacies.

• Primary Classifications: Fallacies are broadly categorized into formal fallacies and informal fallacies.

Classifications of Fallacies: Formal vs. Informal

• Formal Fallacies:

  • Definition: A formal fallacy is one that may be identified just by looking at the structure or form of the argument.

  • Scope: Found exclusively in deductive arguments.

  • Structural Example:

  • Premise 1: All bullfights ($A$) are inhumane ($B$).

  • Premise 2: All executions ($C$) are inhumane ($B$).

  • Conclusion: Therefore, all bullfights ($A$) are executions ($C$).

  • Analysis: The defect is purely structural (invalid syllogistic form, undistributed middle term), regardless of the actual subject matter.

• Informal Fallacies:

  • Definition: An informal fallacy is one that may be detected only by looking at and analyzing the content of the argument.

  • Scope: Found in both deductive and inductive arguments.

  • Content Example:

  • Premise 1: The Brooklyn Bridge is made of atoms.

  • Premise 2: Atoms are invisible.

  • Conclusion: Therefore, the Brooklyn Bridge is invisible.

  • Analysis: Examining the form alone does not reveal the error; understanding the semantic content of "atoms" and their attributes reveals the fallacy (fallacy of composition/division).

Fallacies of Relevance

• General Definition: Fallacies of relevance occur when the premises of an argument are logically irrelevant to the conclusion, even though they may appear to be psychologically relevant to deceive the listener or reader.

• Quantity: There are 8 total fallacies classified under fallacies of relevance.

Detailed Analysis of the Fallacies of Relevance

• Appeal to Force (Argumentum ad Baculum):

  • Nature: Involves a threat by the arguer to the physical or psychological well-being of the listener or reader, whether directed at an individual or a group of people, to compel acceptance of a conclusion.

  • Text Reference: Page 129

• Appeal to Pity (Argumentum ad Misericordiam):

  • Nature: The arguer attempts to support a conclusion by evoking pity or sympathy from the reader or listener, whether directed toward the arguer themselves or toward a third party.

  • Text Reference: Page 130

• Appeal to the People (Argumentum ad Populum):

  • Direct Approach: Occurs when an arguer, addressing a large group of people, excites the emotions and enthusiasm of the crowd to gain acceptance for a conclusion. Includes the appeal to fear as a specific variation of the direct appeal.

  • Indirect Approach: Occurs when the arguer aims their appeal at one or more individuals within a crowd, focusing on some aspect of their relationship to the crowd or social desires.

  • Bandwagon Argument: Appeals to the desire to conform or fit in with the crowd.

  • Appeal to Vanity: Connects the conclusion to an admired person or trait.

  • Appeal to Snobbery: Connects the conclusion to an elite or exclusive group.

  • Appeal to Tradition: Appeals to historical practice or long-standing custom.

• Argument Against the Person (Ad Hominem):

  • General Mechanics: Involves two arguers where the second person attacks the person making the argument rather than addressing the logic or evidence of the argument itself.

• Subtype 1: Abusive

  • Mechanism: The second person responds to the first person's argument by verbally abusing or insulting the first person directly.

  • Text Reference: Pages 134-135

• Subtype 2: Circumstantial

  • Mechanism: The respondent attempts to discredit the opponent's argument by alluding to the opponent's personal circumstances. The respondent attempts to show that the opponent is predisposed to argue the way they do and should therefore not be taken seriously.

  • Text Reference: Page 135

• Subtype 3: Tu Quoque ("You Too")

  • Mechanism: The second arguer attempts to make the first appear hypocritical or to be arguing in bad faith by pointing out that the first arguer acts in a way contrary to their own conclusion.

  • Text Reference: Page 136

  • Accident:

• Nature: Committed when a general rule is applied to a specific case that the general rule was not intended to cover due to accidental or exceptional circumstances.

• Straw Man:

  • Nature: Committed when an arguer distorts an opponent's argument for the purpose of attacking it more easily, demolishes the distorted argument, and then concludes that the opponent's real argument has been demolished.

  • Text Reference: Page 138

• Missing the Point (Ignoratio Elenchi):

  • Nature: Occurs when the premises of an argument logically support one particular conclusion, but then a completely different conclusion, often vaguely related to the correct conclusion, is drawn instead.

  • Text Reference: Page 139

• Red Herring:

  • Nature: Committed when the arguer diverts the attention of the reader or listener by changing the subject to a different, but sometimes subtly related topic, and draws a conclusion based on that new topic.

  • Text Reference: Page 140

Distinguishing Distraction Fallacies: Straw Man, Missing the Point, and Red Herring

• Distinguishing Criteria for Straw Man (SM):

  • Always involves 2 arguers.

  • Distorts the original argument presented by the opponent.

  • Involves introducing new premises based on the distortion.

  • Contains a conclusion that is directly relevant to the new, distorted premises.

• Distinguishing Criteria for Missing the Point (MtP):

  • Involves no new premises beyond those originally stated.

  • Contains an irrelevant conclusion that fails to follow from the original premises.

  • Methodological Rule: Only classify an argument as Missing the Point if no other specific fallacy can be identified.

• Distinguishing Criteria for Red Herring (RH):

  • Ignores the original argument or topic.

  • Changes the topic altogether to a different subject.

  • Contains a conclusion relevant to the new premises introduced during the topic shift.

Fundamentals of Logical Fallacies

• Definition: A defect in reasoning or illusion that makes a bad argument appear good, occurring in both deductive and inductive arguments.

• Primary Classifications: Formal fallacies and informal fallacies.

Classifications of Fallacies: Formal vs. Informal

• Formal Fallacies:

  • Identified purely by logical structure or form; found exclusively in deductive arguments.

  • Example: All bullfights ($A$) are inhumane ($B$); all executions ($C$) are inhumane ($B$); therefore, all bullfights ($A$) are executions ($C$).

• Informal Fallacies:

  • Detected only by analyzing semantic content; found in both deductive and inductive arguments.

  • Example: The Brooklyn Bridge is made of atoms; atoms are invisible; therefore, the Brooklyn Bridge is invisible.

Fallacies of Relevance

• Definition: Group of 8 fallacies where premises are logically irrelevant to the conclusion, despite appearing psychologically relevant.

Detailed Analysis of the Fallacies of Relevance

• Appeal to Force (Argumentum ad Baculum): Uses physical or psychological threats to force acceptance of a conclusion.

• Appeal to Pity (Argumentum ad Misericordiam): Evokes sympathy or pity to support a conclusion.

• Appeal to the People (Argumentum ad Populum):

  • Direct Approach: Excites crowd emotions and enthusiasm (includes appeal to fear).

  • Indirect Approach: Targets individuals using bandwagon, vanity, snobbery, or tradition.

• Argument Against the Person (Ad Hominem):

  • Abusive: Directly insults or verbally abuses the opponent.

  • Circumstantial: Discredits argument by citing the opponent's personal circumstances.

  • Tu Quoque: Accuses the opponent of hypocrisy.

• Accident: Applies a general rule to an exceptional specific case it was not meant to cover.

• Straw Man: Distorts an opponent's argument to attack and defeat a misrepresented version.

• Missing the Point (Ignoratio Elenchi): Premises support one specific conclusion, but a different, irrelevant conclusion is drawn.

• Red Herring: Diverts attention by switching to a different topic and drawing a conclusion on that new topic.

Distinguishing Distraction Fallacies

• Straw Man: Involves 2 arguers; distorts original argument; introduces new premises; conclusion fits distorted premises.

• Missing the Point: Uses no new premises; draws an irrelevant conclusion (applied only when no other fallacy fits).

• Red Herring: Ignores original argument entirely; shifts topic; conclusion fits new topic.